Antiaging, Stress Resistance, and Neuroprotective Efficacies of Cleistocalyx nervosum var. paniala Fruit Extracts Using Caenorhabditis elegans Model

Simple ammonium salt and sigma-1 receptor ligand dipentylammonium provides neuroprotective effects in cell culture and Caenorhabditis elegans models of Alzheimer's disease

The sigma-1 receptor (σ-1R), a chaperone protein located at the mitochondria-associated membrane (MAM) of the endoplasmic reticulum, can interact with and modify the signaling pathways of various proteins, thereby modulating many disease pathologies, including Alzheimer's disease (AD). The σ-1R ligand dipentylammonium (DPA) was analyzed for its anti-AD properties using PC12 cells (in vitro) and Caenorhabditis elegans (in vivo) models along with molecular docking (in silico) analysis. DPA at 1 and 10 µM concentrations was able to significantly potentiate NGF-induced neurite growth length by 137.7 ± 12.0 and 187.8 ± 16.4, respectively, when compared to the control 76.9 ± 7.4. DPA also regulated neurite damage caused by Aβ(25-35) treatment in differentiated PC12 cells by improving cell viability and neurite length. In C. elegans, DPA could significantly extend the median and maximum lifespan of Aβ transgenic strain CL2006 without impacting wild-type nematodes. Additionally, it could significantly reduce the paralysis phenotype of another Aβ transgenic strain, CL4176, thereby improving the overall health in AD pathogenesis. This effect depended on σ-1R, as DPA could not modulate the lifespan of σ-1R mutant TM3443. This was further confirmed using agonist PRE084 and antagonist BD1047, wherein the agonist alone could extend the lifespan of CL2006, while the antagonist suppressed the effect of DPA in CL2006. Interestingly, neither had an TM3443. Further, molecular docking analysis showed that DPA had a similar binding affinity as that of PRE084, BD1047 and pentazocine against the σ-1R receptor in humans and C. elegans, which collectively suggests the anti-AD properties of DPA.

Lactobacillus paracasei HII01 enhances lifespan and promotes neuroprotection in Caenorhabditis elegans

Achieving healthy aging and providing protection from aging-related diseases is a major global concern. Probiotics, are a safer and more natural alternative. Moreover, identifying novel probiotics can help develop a new therapeutic approach and may help in personalized probiotic-formulations for individual's unique gut microbiome. In this study, we evaluated the benefits of our novel probiotic strains in promoting healthy aging and whether they protect against Amyloid β toxicity of Alzheimer's disease. Henceforth, we analyzed the impact of four different probiotics (Lactobacillus paracasei HII01, L. rhamnosus, L. reuteri, L. salivarius) on the lifespan extension of Caenorhabditis elegans model. Our results determine that L. paracasei HII01 provided the most positive effect on longevity and antiaging effects on C. elegans. The qPCR data and mutant-based studies indicated that L. paracasei HII01-mediated lifespan extension could be modulated by DAF-16 mediated pathway. The probiotic strains also protected the worms from the toxicity induced by β-Amyloid-expressing (Aβ) transgenic C. elegans strains, and L. paracasei HII01 provided the most significant protection. Overall, identifying novel probiotics is an important area of research that can improve health outcomes. Our study showed that L. paracasei HII01 could be considered a dietary supplement for providing healthy aging and preventing aging-related diseases.

Rose essential oil diminishes dopaminergic neuron degenerations and reduces α-synuclein aggregation in Caenorhabditis elegans models of Parkinson's disease

Parkinson's disease (P.D.) is the second most progressive neurodegenerative disorder in the elderly. Degeneration of dopaminergic (DA) neurons and α-synuclein (α-Syn) accumulated toxicity is the major contributor to this disease. At present, the disease has no effective treatment. Many recent studies focus on identifying novel therapeutics that provide benefits to stop the disease progression in P.D. patients. Screening novel and effective drugs in P.D. animal models is time- and cost-consuming. Rose Essential Oil (REO) extracted from Rosa Rugosa species (R. Setate × R. Rugosa). REO contains Citronellol, Geraniol, and Octadiene that possess anti-Aβ, anti-oxidative, and anti-depression-like properties, but no reports have defined the REO effect on P.D. yet. The present study examines the REO neuroprotective potential in transgenic Caenorhabditis elegans P.D. models. We observed that REO reduced α-Syn aggregations and diminished DA neuron degenerations induced by 6-OHDA, reduced food-sensing behavioural disabilities, and prolonged the lifespan of the nematode. Moreover, REO augmented the chymotrypsin-like proteasome and SOD-3 activities. Further, we observed the anti-oxidative role of REO by reducing internal cells ROS. Together, these findings supported REO as an anti-PD drug and may exert its effects by lowering oxidative stress via the anti-oxidative pathway.

Effects of Vegetal Extracts and Metabolites against Oxidative Stress and Associated Diseases: Studies in Caenorhabditis elegans

Oxidative stress is a natural physiological process where the levels of oxidants, such as reactive oxygen species (ROS) and nitrogen (RNS), exceed the strategy of antioxidant defenses, culminating in the interruption of redox signaling and control. Oxidative stress is associated with multiple pathologies, including premature aging, neurodegenerative diseases, obesity, diabetes, atherosclerosis, and arthritis. It is not yet clear whether oxidative stress is the cause or consequence of these diseases; however, it has been shown that using compounds with antioxidant properties, particularly compounds of natural origin, could prevent or slow down the progress of different pathologies. Within this context, the Caenorhabditis elegans (C. elegans) model has served to study the effect of different metabolites and natural compounds, which has helped to decipher molecular targets and the effect of these compounds on premature aging and some diseases such as neurodegenerative diseases and dyslipidemia. This article lists the studies carried out on C. elegans in which metabolites and natural extracts have been tested against oxidative stress and the pathologies associated with providing an overview of the discoveries in the redox area made with this nematode.

In Vitro Evaluation of Antidiabetic Potential of Cleistocalyx nervosum var. paniala Fruit Extract

Diabetes mellitus is a complex global public health condition. Medicinal plants are significant resources in the research of alternative new drug active compounds. Cleistocalyx nervosum var. paniala (C. nervosum) is an indigenous berry fruit widely grown in Southeast Asia. The fruit of C. nervosum exhibit various medicinal properties and health benefits. This study aimed to investigate antidiabetic properties of C. nervosum fruit extract by in vitro assays and in vitro models. C. nervosum fruit extracted using three different solvents (hexane, ethanol, and distilled water) were tested for α-amylase and α-glucosidase inhibitory activities, followed by glucose uptake in HepG2 and L6 myoblasts. Lipid accumulation in 3T3-L1 cells treated with C. nervosum fruit extracts was then examined. The results revealed that ethanolic extract of C. nervosum fruit showed better inhibition against α-amylase (IC₅₀ of 0.42 μg/mL) and α-glucosidase (IC₅₀ of 0.23 μg/mL) compared with other extracts. Furthermore, ethanolic extract showed higher glucose uptake potential than the standard antidiabetic drug, metformin, in HepG2 cells. The ethanolic extracts resulted in enhanced glucose utilization in L6 myoblasts compared to untreated control. All extractions showed no significantly increased lipid accumulation in 3T3-L1 cells compared to the untreated control cells. The investigation confirmed that the ethanolic extract exhibited the highest antidiabetic activity among all extracts. These results imply that C. nervosum fruit extract has antidiabetic properties and therefore they may be used as useful therapeutic agents for treating diabetes.

Cleistocalyx nervosum var. paniala Berry Promotes Antioxidant Response and Suppresses Glutamate-Induced Cell Death via SIRT1/Nrf2 Survival Pathway in Hippocampal HT22 Neuronal Cells

Excessive glutamate neurotransmitters result in oxidative neurotoxicity, similar to neurodegeneration. An indigenous berry of Thailand, Cleistocalyx nervosum var. paniala (CNP), has been recognized for its robust antioxidants. We investigated the effects and mechanisms of CNP fruit extracts on antioxidant-related survival pathways against glutamate-induced neurotoxicity. The extract showed strong antioxidant capability and had high total phenolic and flavonoid contents, particularly resveratrol. Next, the protective effects of the CNP extract or resveratrol on the glutamate-induced neurotoxicity were examined in HT22 hippocampal cells. Our investigation showed that the pretreatment of cells with the CNP extract or resveratrol attenuated glutamate-induced neuronal death via suppression of apoptosis cascade by inhibiting the levels of cleaved- and pro-caspase-3 proteins. The CNP extract and resveratrol suppressed the intracellular ROS by increasing the mRNA expression level of antioxidant enzymes (SODs, GPx1, and CAT). We found that this extract and resveratrol significantly increased SIRT1 expression as a survival-related protein. Moreover, they also promoted the activity of the Nrf2 protein translocation into the nucleus and could bind to the promoter containing the antioxidant response element, inducing the expression of the downstream GPx1-antioxidant protein. Our data illustrate that the CNP extract and resveratrol inhibit apoptotic neuronal death via glutamate-induced oxidative neurotoxicity in HT22 cells through the activation of the SIRT1/Nrf2 survival mechanism.

Aquilaria crassna Leaf Extract Ameliorates Glucose-Induced Neurotoxicity In Vitro and Improves Lifespan in Caenorhabditis elegans

Hyperglycemia is one of the important causes of neurodegenerative disorders and aging. Aquilaria crassna Pierre ex Lec (AC) has been widely used to relieve various health ailments. However, the neuroprotective and anti-aging effects against high glucose induction have not been investigated. This study aimed to investigate the effects of hexane extract of AC leaves (ACH) in vitro using human neuroblastoma SH-SY5Y cells and in vivo using nematode Caenorhabditis elegans. SH-SY5Y cells and C. elegans were pre-exposed with high glucose, followed by ACH treatment. To investigate neuroprotective activities, neurite outgrowth and cell cycle progression were determined in SH-SY5Y cells. In addition, C. elegans was used to determine ACH effects on antioxidant activity, longevity, and healthspan. In addition, ACH phytochemicals were analyzed and the possible active compounds were identified using a molecular docking study. ACH exerted neuroprotective effects by inducing neurite outgrowth via upregulating growth-associated protein 43 and teneurin-4 expression and normalizing cell cycle progression through the regulation of cyclin D1 and SIRT1 expression. Furthermore, ACH prolonged lifespan, improved body size, body length, and brood size, and reduced intracellular ROS accumulation in high glucose-induced C. elegans via the activation of gene expression in the DAF-16/FoxO pathway. Finally, phytochemicals of ACH were analyzed and revealed that β-sitosterol and stigmasterol were the possible active constituents in inhibiting insulin-like growth factor 1 receptor (IGFR). The results of this study establish ACH as an alternative medicine to defend against high glucose effects on neurotoxicity and aging.

The endophytic fungus Penicillium oxalicum isolated from Ligusticum chuanxiong Hort possesses DNA damage-protecting potential and increases stress resistance properties in Caenorhabditis elegans

The chemical composition and antioxidant activity of extracts (POE) of Penicillium oxalate isolated from Ligusticum chuanxiong Hort have been investigated. However, the biological activity of POE is limited, and its antioxidant, stress resistance and DNA protection effects in vivo are unclear. The current study aims to explore the beneficial effects of POE on DNA damage protection in pBR322 plasmid and lymphocytes and stress resistance in Caenorhabditis elegans. The results showed that POE increased the survival rate of C. elegans under 35°C, UV and H₂O₂ stress, attenuated ROS and MDA accumulation, and enhanced the activity of some important enzymes (SOD, CTA, and GSH-PX). In addition, the POE-mediated stress resistance involved the upregulation of the expression of the sod-3, sod-5, gst-4, ctl-1, ctl-2, daf-16, hsp-16.1, hsp-16.2, and hsf-1 genes and acted dependently on daf-16 and hsf-1 rather than skn-1. Moreover, POE also reduced lipofuscin levels, but did not prolong the lifespan or damage the growth, reproduction and locomotion of C. elegans. Furthermore, POE showed a protective effect against DNA scission in the pBR322 plasmid and lymphocytes. These results suggested that P. oxalate extracts have significant anti-stress and DNA protection potential and could be potential drug candidates in the pharmaceutical field, thus greatly broadening the understanding of the biological effects of the endophytic fungus P. oxalate.

Oxidation and Antioxidation of Natural Products in the Model Organism Caenorhabditiselegans

Natural products are small molecules naturally produced by multiple sources such as plants, animals, fungi, bacteria and archaea. They exert both beneficial and detrimental effects by modulating biological targets and pathways involved in oxidative stress and antioxidant response. Natural products’ oxidative or antioxidative properties are usually investigated in preclinical experimental models, including virtual computing simulations, cell and tissue cultures, rodent and nonhuman primate animal models, and human studies. Due to the renewal of the concept of experimental animals, especially the popularization of alternative 3R methods for reduction, replacement and refinement, many assessment experiments have been carried out in new alternative models. The model organism Caenorhabditis elegans has been used for medical research since Sydney Brenner revealed its genetics in 1974 and has been introduced into pharmacology and toxicology in the past two decades. The data from C. elegans have been satisfactorily correlated with traditional experimental models. In this review, we summarize the advantages of C. elegans in assessing oxidative and antioxidative properties of natural products and introduce methods to construct an oxidative damage model in C. elegans. The biomarkers and signaling pathways involved in the oxidative stress of C. elegans are summarized, as well as the oxidation and antioxidation in target organs of the muscle, nervous, digestive and reproductive systems. This review provides an overview of the oxidative and antioxidative properties of natural products based on the model organism C. elegans.

Current Understanding of Modes of Action of Multicomponent Bioactive Phytochemicals: Potential for Nutraceuticals and Antimicrobials

Plants produce a diversity of plant secondary metabolites (PSMs), which function as defense chemicals against herbivores and microorganisms but also as signal compounds. An individual plant produces and accumulates mixtures of PSMs with different structural features using different biosynthetic pathways. Almost all PSMs exert one or several biological activities that can be useful for nutrition and health. This review discusses the modes of action of PSMs alone and in combinations. In a mixture, most individual PSMs can modulate different molecular targets; they are thus multitarget drugs. In an extract with many multitarget chemicals, additive and synergistic effects occur. Experiments with the model system Caenorhabditis elegans show that polyphenols and carotenoids can function as powerful antioxidative and longevity-promoting PSMs. PSMs of food plants and spices often exhibit antioxidant, anti-inflammatory, and antimicrobial properties, which can be beneficial for health and the prevention of diseases. Some extracts from food plants and spices with bioactive PSMs have potential for nutraceuticals and antimicrobials.

HydroZitLa inhibits calcium oxalate stone formation in nephrolithic rats and promotes longevity in nematode Caenorhabditis elegans

Low fluid intake, low urinary citrate excretion, and high oxidative stress are main causative factors of calcium oxalate (CaOx) nephrolithiasis. HydroZitLa contains citrate and natural antioxidants and is developed to correct these three factors simultaneously. Antioxidants theoretically can prolong the lifespan of organisms. In this study, we preclinically investigated the antilithogenic, lifespan-extending and anti-aging effects of HydroZitLa in HK-2 cells, male Wistar rats, and Caenorhabditis elegans. HydroZitLa significantly inhibited CaOx crystal aggregation in vitro and reduced oxidative stress in HK-2 cells challenged with lithogenic factors. For experimental nephrolithiasis, rats were divided into four groups: ethylene glycol (EG), EG + HydroZitLa, EG + Uralyt-U, and untreated control. CaOx deposits in kidneys of EG + HydroZitLa and EG + Uralyt-U rats were significantly lower than those of EG rats. Intrarenal expression of 4-hydroxynonenal in EG + HydroZitLa rats was significantly lower than that of EG rats. The urinary oxalate levels of EG + HydroZitLa and EG + Uralyt-U rats were significantly lower than those of EG rats. The urinary citrate levels of EG + HydroZitLa and EG + Uralyt-U rats were restored to the level in normal control rats. In C. elegans, HydroZitLa supplementation significantly extended the median lifespan of nematodes up to 34% without altering feeding ability. Lipofuscin accumulation in HydroZitLa-supplemented nematodes was significantly lower than that of non-supplemented control. Additionally, HydroZitLa inhibited telomere shortening, p16 upregulation, and premature senescence in HK-2 cells exposed to lithogenic stressors. Conclusions, HydroZitLa inhibited oxidative stress and CaOx formation both in vitro and in vivo. HydroZitLa extended the lifespan and delayed the onset of aging in C. elegans and human kidney cells. This preclinical evidence suggests that HydroZitLa is beneficial for inhibiting CaOx stone formation, promoting longevity, and slowing down aging.

Ethnopharmacology, Phytochemistry, and Pharmacology of Syzygium nervosum

Syzygium nervosum, which belongs to the Myrtaceae plant family, is widely distributed and cultivated in South East Asian countries. The decoction of S. nervosum leaves and flower buds has been consumed regularly as a beverage among the Vietnamese and Chinese communities. In addition, it has also been used in traditional medicine for a variety of purposes, notably for influenza, skin diseases, and digestive conditions. To date, there has been a considerable number of publications on chemical profiling and pharmacological activities of S. nervosum crude extract and pure isolated compounds. Our analysis indicated the characteristic chemical scaffolds and potential bioactivities on cancer, diabetes, and inflammatory diseases of this plant. The review aims to summarize up-to-date past study results and suggest future research direction on this species, in order to promote clinical applications of S. nervosum.

Paper-Based Analytical Device for Real-Time Monitoring of Egg Hatching in the Model Nematode Caenorhabditis elegans

Caenorhabditis elegans is an in vivo model known for its easy handling and maintenance and lack of associated ethical issues. The release of chitinase can be used to monitor the egg-laying stage in C. elegans. The aim of this study was to develop a simple and cost-effective device to monitor the activity of chitinase in embryos of C. elegans. Colloid chitin azure (CCA), a substrate for chitinase, was preimmobilized on the detection area of paper, forming a purple region, to generate a CCA paper-based analytical device (CCA-PAD). The degradation of CCA by chitinase could be observed as the purple color became faint and the filter paper eventually became colorless. Under the optimum conditions, the proposed device quantified the chitinase enzyme in the range of 15.625-125 mU/mL within 48 h (R² = 0.993). In this work, 10 young adult-staged wild-type C. elegans (Bristol N2) worms were analyzed on the CCA-PAD, which was supplemented with the laboratory food source E. coli OP50 on a gauze layer. The same strain treated with 5-fluoro-2'-deoxyuridine was used to prevent egg production in C. elegans. A significant difference in the color intensity was observed between these two groups at the end of the experiment (P = <0.001, independent t-test, n = 3). We successfully developed a simple and effective method for monitoring chitinase activity. The device may have potential applications in drug-screening studies as it efficiently distinguishes drugs that can impact egg laying.

Potential Thai medicinal plants for neurodegenerative diseases: A review focusing on the anti-glutamate toxicity effect

Neurodegenerative diseases (NDD) are a range of debilitating conditions of the brain involving progressive loss of neurons, many of which are still currently incurable despite enormous efforts on drug discovery and development in the past decade. As NDD is closely linked to old age, the rapid worldwide growth in the aging population contributes to an increasing number of people with one of these incurable diseases and therefore it is considered a significant global health issue. There is an urgent need for novel effective treatments for NDD, and many new research strategies are centered on traditional medicine as an alternative or complementary solution. Several previous findings have suggested that glutamate toxicity drives neurodegeneration in many NDD, and the medicinal plants with anti-glutamate toxicity properties can be potentially used for their treatment. In order to obtain data relating to natural products against glutamate toxicity, six candidate plant species of Thailand were identified. Studies utilizing these herbs were searched for using the herb name (Latin and common names) along with the term "glutamate" in the following databases across all available years: PubMed, Scopus, and Google Scholar. This review emphasizes the importance of glutamate toxicity in NDD and summarizes individual plants and their active constituents with the mechanism of action against glutamate toxicity-mediated neuronal cell death that could be a promising resource for future NDD therapy.

TAXONOMY CLASSIFICATION BY EVISE

Alzheimer's disease, Neurodegenerative diseases, Cell culture, Molecular Biology, Traditional herbal medicine, Oxidative stress, Glutamate neurotransmitter.

Potential Protective Role Exerted by Secoiridoids from Olea europaea L. in Cancer, Cardiovascular, Neurodegenerative, Aging-Related, and Immunoinflammatory Diseases

Iridoids, which have beneficial health properties, include a wide group of cyclopentane [c] pyran monoterpenoids present in plants and insects. The cleavage of the cyclopentane ring leads to secoiridoids. Mainly, secoiridoids have shown a variety of pharmacological effects including anti-diabetic, antioxidant, anti-inflammatory, immunosuppressive, neuroprotective, anti-cancer, and anti-obesity, which increase the interest of studying these types of bioactive compounds in depth. Secoiridoids are thoroughly distributed in several families of plants such as Oleaceae, Valerianaceae, Gentianaceae and Pedialaceae, among others. Specifically, Olea europaea L. (Oleaceae) is rich in oleuropein (OL), dimethyl-OL, and ligstroside secoiridoids, and their hydrolysis derivatives are mostly OL-aglycone, oleocanthal (OLE), oleacein (OLA), elenolate, oleoside-11-methyl ester, elenoic acid, hydroxytyrosol (HTy), and tyrosol (Ty). These compounds have proved their efficacy in the management of diabetes, cardiovascular and neurodegenerative disorders, cancer, and viral and microbial infections. Particularly, the antioxidant, anti-inflammatory, and immunomodulatory properties of secoiridoids from the olive tree (Olea europaea L. (Oleaceae)) have been suggested as a potential application in a large number of inflammatory and reactive oxygen species (ROS)-mediated diseases. Thus, the purpose of this review is to summarize recent advances in the protective role of secoiridoids derived from the olive tree (preclinical studies and clinical trials) in diseases with an important pathogenic contribution of oxidative and peroxidative stress and damage, focusing on their plausible mechanisms of the action involved.